The objectives of the Core facility are: 1) to provide centralized facilities for exposing animals and cell cultures to intermitten hypoxia for investigations in all the projects; 2) to provide centralized facility for reagents, antibodies and restriction enzymes; 3) to share personnel for tissue processing as well as major equipment such as confocal microscope, electron microscope, 4) to share the cost and utilize effectively the data from micro array analysis; 5) to incorporate the experimental results into mathematical models that provide feedback for further refining the experimental design as well as hypotheses.